The importance of urban planning on air quality and human health

Air pollution in Europe is one of the environmental factors that contribute the most to environment-related diseases. An evaluation made by the World Health Organization (WHO) [WHO, 2004] suggests that air pollution is responsible, each year, for 100.000 deaths in the largest European cities. Besides that recent studies have shown that different city structures have different implications on air quality [e.g. Lyons et al., 2003; Borrego et al., 2006]. The SaudAr project, presented in this work, was idealized to better understand the relation air pollution-health and shed some light on how to minimize those health impacts. The main objective was to study the air quality effects on health in a population group risk (school children) living in an urban area not yet polluted, but for which is foreseen an important development with possible environmental problems. Then, a case study was selected based on the ten most important Portuguese towns located on the inland part of the country, where a better air quality and population health are expected, and where the existing development dynamics suggest an environmental degradation in the near future. The city of Viseu was selected as case study, because of its strategic location in the central Portuguese mainland, very close to important road transport networks and its high projected development. The local municipality strategic development plan establishes the placement of different activities, the changes in land use, and defines the foreseen structural dynamics, such as road transport networks, housing or industrial areas. Based on those features and on several discussion with local authorities (namely the municipality planning department), future scenarios of urban sprawl were designed, using social, economic, demographic, technological and urban development indicators. These scenarios have then been translated into air pollutant emissions scenarios to assess future air quality on the region as well as human exposure. Numerical tools were applied to estimate air quality and human exposure changes related with the future scenarios. This methodology allowed to: 1) analyze the consequences on respiratory human health due to exposure to pollutants concentration; 2) investigate the impacts of future scenarios on air quality and human health; 3) define guidelines for local development plans. The results of all the developed scenarios show that the most critical pollutant in Viseu is PM₁₀, similarly to what was verified in the current situation. However, the scenarios results allowed to conclude that the compact city has the lowest absolute emissions than disperse one, but the higher emissions per area. This results in higher human exposure in the compact city. The information obtained from SaudAr project has a significant interest to help the municipal authorities to prevent air pollution and population health problems in the future and it may be used to redefine the town strategic plan.